The transport of heat to the Norwegian and Barents Seas is essential for the living conditions in northern Europe. The inflow of Atlantic Water through the Greenland-Shetland section also strongly influences the ocean circulation on the continental shelves in the region. Knowledge of the variability of this inflow is important for evaluations of climate change and the interpretation of how representative ocean conditions are during limited field studies.

MAIA (Monitoring the Atlantic Inflow toward the Arctic) is a European Union funded project involving six partners: SINTEF Fishery and Aquaculture and the Institute of Marine Research (Norway), Swedish Meteorological and Hydrological Institute, Université Pierre et Marie Curie (France) and NERC Proudman Oceanographic Laboratory and Aberdeen Fisheries Research (U.K.). MAIA has as its main objective the development of an inexpensive, reliable system for monitoring the inflow of Atlantic water to the northern seas, based on coastal sea-level data, and to investigate how the changing ice extent in the north is related to this flux.

Available observation systems, including standard tidal stations, are used to obtain transport estimates with a time resolution of less than a week and to show to what degree the method is accurate and applicable to the monitoring of other regions. Figure 1 represents the study site of the MAIA project, indicating tidal stations from which coastal water level data are extracted. Flux is calculated from coastal water level data by employing the principal of geostrophy.

The ice cover is an important component of the Arctic climate system. Long-term variations in the ice front, or Marginal Ice Zone (MIZ), in the Barents Sea are a measure of climate variability. The location of the MIZ is also a good indicator for predicting the routes and strengths of the Atlantic heat flux. From passive microwave data Parkinson et. al (1999) states that the horizontal ice extent, that is ice concentration, for the whole Arctic has decreased by 2.8 % per decade during 1978-1996. Further, the decline is especially pronounced in the Barents and Kara Seas. During 1978-1996 the annual decrease of the ice extent was 11.7 % in those seas. However, the interannual variation is large. In fact, during the 1990-1996, the trend for the Arctic is positive. Indeed, the ice front in the Barents Sea is an indicator of climatic variability. Sea ice is a physical parameter better suited to satellite sensing than to traditional ship measurements since the cold offshore environment is a rough place to work in.

The aim of the study was to measure relative changes in the ice front motions in relation to the flux of Atlantic water and various other oceanographic and meteorological parameters.
Our method to study the sensitivity of the sea ice in the Barents Sea to external forcing included a validation of the SSM/I dataset. This dataset has outstanding temporal resolution. It was validated for the MIZ in the Barents Sea using SAR images with very high spatial resolution. The validation gave good results, and confidence for further work with the sensitivity analysis. A significant negative correlation between the Atlantic inflow and the sea ice in the western Barents Sea during winters was found using a time resolution of 1 day. Our analysis shows that the ice in the western Barents Sea does not get more compact when the sea ice extent increases, which is the case in the eastern Barents Sea.